1. Field of the Invention
This invention is related to welds between steel work pieces and, more particularly, to parts with coatings applied to weld seams between steel work pieces.
2. Related Art
Gas-metal arc welding (GMAW), which is also known as metal inert gas (MIG) welding, is commonly employed to weld steel work pieces together in the automotive industry. A common problem with employing GMAW to join steel work pieces is the development of silicate islands of manganese, silicone, iron, oxygen and other trace alloys. Such silicate islands may inhibit the application of a coating onto the outer surface of the weld seam. For example, coatings applied through painting, phosphating and electrocoating (e-coating) may not adhere strongly to weld seams with silicate islands.
One approach to removing the silicate islands from the weld seams of GMAW welds is to use a material abrasion process to remove the silicate islands. However, this approach requires significant consumable costs and capital. Another approach is to use chemical processes. However, chemical processes also may be costly and may not result in sufficient removal of the silicate islands from the weld seam.
There remains a significant and continuing need for an improved process to remove silicate islands from the weld seams of GMAW welds.